| /* |
| * Copyright 2017 Google Inc. All Rights Reserved. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef NB_BIDIRECTIONAL_FIT_REUSE_ALLOCATOR_H_ |
| #define NB_BIDIRECTIONAL_FIT_REUSE_ALLOCATOR_H_ |
| |
| #include "nb/reuse_allocator_base.h" |
| #include "starboard/configuration.h" |
| |
| namespace nb { |
| |
| // This class uses first-fit allocation strategy to allocate memory block whose |
| // size is greater than the |small_allocation_threshold|. It uses last-fit |
| // strategy to allocate memory block whose size is less than or equal to the |
| // |small_allocation_threshold|. This allows better fragmentation management. |
| // If fragmentation is not an issue, FirstFitReuseAllocator might be a simpler |
| // alternative. |
| // Note that when using this class a significant |initial_capacity| should be |
| // set as otherwise new allocations will almost always allocate from the front |
| // of the fallback allocator. |
| class BidirectionalFitReuseAllocator : public ReuseAllocatorBase { |
| public: |
| BidirectionalFitReuseAllocator(Allocator* fallback_allocator, |
| std::size_t initial_capacity, |
| std::size_t small_allocation_threshold, |
| std::size_t allocation_increment = 0); |
| |
| FreeBlockSet::iterator FindFreeBlock(std::size_t size, |
| std::size_t alignment, |
| FreeBlockSet::iterator begin, |
| FreeBlockSet::iterator end, |
| bool* allocate_from_front) SB_OVERRIDE; |
| |
| private: |
| std::size_t small_allocation_threshold_; |
| }; |
| |
| } // namespace nb |
| |
| #endif // NB_BIDIRECTIONAL_FIT_REUSE_ALLOCATOR_H_ |